Hardware Today: Turning on SAN Switches Page 2

Building on its network switch success, Cisco has entered the storage switch market with a vengeance. From a 5.9 percent market share in 2003 to 14.9 percent last year, Cisco has recorded quarterly market share as high as 20 percent. Like its rivals, Cisco is talking up increased intelligence in the SAN fabric and lower costs.

The network is the ideal place for adding intelligence to enable certain applications, such as data migration, volume management, and backup acceleration, says Paul Dul, director product management at Ciscos data center and storage business unit. Multiprotocol SANs are now a reality with all major SAN switch vendors at the very least announcing plans to support transport protocols beyond Fibre Channel.

Cisco was the first vendor to make multiprotocol SANs available through a wide variety of interface modules and multiprotocol chassis options. The MDS 9020 Fabric Switch is a low-end offering with 4 Gbps performance on 20 ports, for an aggregate bandwidth of 160 Gbps.

In the midrange, the Cisco MDS 9216i Multilayer Fabric Switch integrates FC and IP into a single form factor. It provides 14 2-Gbps FC interfaces and two Gigabit Ethernet ports that can be configured to support either FC over IP (FCIP) for long distance SAN extension or iSCSI for cost-effective SAN expansion. In the director class, the Cisco MDS 9509 Multilayer Director supports 16 to 224 1/2-Gbps auto-sensing FC ports or eight to 48 1-Gbps Ethernet ports in a nine-slot modular chassis. That means up to 672 FC ports in a single rack.

The Others

Collectively, Brocade, McData, and Cisco account for more than 90 percent of the pie. Next in line come QLogic (4.5 percent), CNT (4.1 percent, and recently acquired by McData), Emulex (0.3 percent ) as well as startups, such as Troika Networks (just gobbled up by QLogic) and Maxxan, which are focusing on the red-hot intelligent switch space.

Maxxan believes that intelligence and integration of functions are among the key trends emerging at the switch level.

User surveys have shown that users have a clear preference for an integrated approach to storage network services that avoids the need to deploy a multitude of devices, says Greg Farris, senior product Manager at Maxxan.

He gives the example of storage security services. There is a clear need to encrypt sensitive stored data, but, he says, the options to this point have not been satisfactory. Users with larger data centers have had only the options of using software encryption that exacts a severe performance penalty or deploying a rack full of expensive appliances that do not provide adequate scalability. He believes most enterprises would prefer an integrated service in an intelligent switching platform that can scale in performance to meet their needs.

Another example is storage virtualization integration, says Farris. While some users have adopted external appliances, we believe more will be interested in evaluating a solution that integrates transparently with other services.

To meet these needs, the Maxxan MXV250 scales from 16 to 64 ports within a single, centrally managed chassis. It has the ability to function either as a SAN switch that supports storage applications or as a storage application platform to support applications, such as storage security, storage virtualization, snapshots, data replication, and NAS as network services. The Maxxan MXV500, on the other hand, is a higher-end model. It supports 16 to 256 ports, as well as 512 ports in a second chassis.

4 Gb Delays

Most of the vendors mentioned in this article have either announced or shipped 4 Gb technology. Tam DellOro warns, however, that there have be some company-specific glitches to these newer products, andrelatively few have made it into a production environment.

SANs are often used to back up the crown jewels so these companies cant afford them going down, says DellOro.

As a result, 4 Gb geargenerally undergoes rigorous testing from large systems integration firms before enterprises permit them to be deployed with mission-critical applications.Once a vendor proves its mettle in terms of reliability, redundancy, and resiliency, she foresees a rapid adoption curve.

Although users are cautious, I expect to see strong demand for 4 GB and strong demand for switches due to corporate demand and legislative pressure, says DellOro. But it will take another six to nine months to complete ongoing testing.